1. Technical Field
The present invention relates to a resonator element, a resonator, an oscillator, an electronic apparatus, and a moving object.
2. Related Art
A resonator element using crystal is known. Such a resonator element has an excellent frequency-temperature characteristic. Accordingly, the resonator element is widely used as a reference frequency source, a signal transmission source, or the like of various electronic apparatuses. The resonator element disclosed in JP-A-2011-19159 is of a tuning fork type, and includes a base portion and a pair of vibrating arms extending from the base portion. In addition, in order to reduce the size and improve the vibration characteristics, a weight portion (wide portion) called a hammerhead is formed at the distal end of each vibrating arm. For example, the length of the hammerhead is set to 30% or more of the total length of the vibrating arm in JP-A-2011-19159, and the length of the hammerhead is set to 35% to 41% of the total length of the vibrating arm in JP-A-2011-199331 and JP-A-2012-129904. However, if the length of the hammerhead is too great for the total length of the vibrating arm as in JP-A-2011-19159, JP-A-2011-199331, and JP-A-2012-129904, when the vibrating arm bends and vibrates, a region where the vibrating arm bends and deforms greatly, that is, a region of an arm portion having a smaller width than the wide portion, which is a region where electrically efficient excitation can be performed, is reduced. As a result, since the CI value of the resonator element becomes high, vibration loss is increased.